Temnothorax agavicola, Prebus, 2021

Prebus, Matthew M., 2021, Taxonomic revision of the Temnothorax salvini clade (Hymenoptera: Formicidae), with a key to the clades of New World Temnothorax, PeerJ (e 11514) 9, pp. 1-462 : 259-264

Temnothorax agavicola sp. nov.

Distribution: Fig. 133A ; worker, gyne & variability: Fig. 134 .

Type material examined: Holotype worker: DOMINICAN REPUBLIC: Pedernales: Jaragua National Park 18.02571 ° N 71.64732 ° W ± 5 m, 92 m 1 April 2012, D. Lubertazzi #DL03475:001 , dry forest, downed wood ( MCZENT00510559 ) [ MCZC].

Paratype workers and gynes: same data as holotype, except: D. Lubertazzi #DL03479:003, dry forest, under Agave, 4 workers & 1 dealate gyne (MCZENT00510560- MCZENT00510562) [ MCZC]; same data as holotype, except: D. Lubertazzi #DL03474:003, dry forest, downed wood, 1 dealate gyne (MCZENT00510541) [ MCZC] .

Non-type material examined: DOMINICAN REPUBLIC: Barahona: 28 km N Barahona, 165 m, 18 August 1988, M.A. Ivie, T.K. Philips & K.A. Johnson, ex rotten agave, 1 worker (CASENT0758360) [ USNM] . TURKS AND CAICOS ISLANDS: Providenciales: Old Airport Road , 21.775 ° N 72.261 ° W, 5 m, 9 July 2010, J.K. Wetterer #JKW-2010-154, tropical scrub by store, 1 worker (CASENT0756096) [ MCZC] 1 worker (CASENT0758672) [ UCDC] 1 worker (CASENT0758819) [ USNM] .

Geographic range: Low elevations of Hispaniola and the Turks and Caicos Islands ( Fig. 133A ).

Worker diagnosis: Temnothorax agavicola sp. nov. can be separated from all other species in the salvini clade by the following character combination: head in full face view with posterior margin weakly concave; mesosoma moderately compact; in profile view, dorsum of mesosoma weakly convex; metanotal groove not impressed; propodeum not depressed below the level of the promesonotum; propodeal spines about as long as the propodeal declivity, directed posteriorly, and straight; hind femora moderately incrassate; in dorsal view, propodeal spines broadly approximated basally, the negative space between them “U” shaped; in dorsal view, apex of petiolar node narrower than the caudal cylinder of the petiole; petiolar node flat dorsally; petiolar node with four erect setae dorsally; postpetiole very broad: greater than 2.6 times the width of the petiole; dorsum of head uniformly areolate; setae on head, mesosoma, waist segments and gaster erect, moderately long, sparse and blunt (never long and tapering); integument light yellow.

Similar species: Temnothorax albispinus , T. laticrus sp. nov., T. torrei , T. wettereri sp. nov., and members of the pastinifer group. Temnothorax agavicola sp. nov. can be separated from all members of the pastinifer group by the apically narrow petiolar node, which not squamiform and always narrower than the caudal cylinder of the petiole in dorsal view. The propodeal spines, which are longer than the propodeal declivity and relatively narrow hind femora will distinguish T. agavicola sp. nov. from T. laticrus sp. nov., which has propodeal spines that are shorter than the declivity and extremely incrassate hind femora. The erect setae count of four on the dorsum of the petiolar node differentiates T. agavicola sp. nov. from T. torrei , which has only two along the posterior margin. The weakly concave posterior margin of the head of T. agavicola sp. nov. contrasts with T. albispinus , which has a flat to weakly convex posterior head margin. The body of T. wettereri sp. nov. is mostly devoid of erect setae, whereas T. agavicola sp. nov. has more than ten erect setae on the dorsum of the mesosoma.

Worker measurements & indices (n = 9): SL = 0.474 –0.500 (0.486); FRS = 0.169 –0.199 (0.182); CW = 0.516 –0.588 (0.552); CWb = 0.478 –0.544 (0.509); PoOC = 0.248 –0.267 (0.260); CL = 0.593 –0.655 (0.626); EL = 0.121 –0.145 (0.132); EW = 0.093 –0.105 (0.101); MD = 0.136 –0.159 (0.148); WL = 0.663 –0.750 (0.700); SPST = 0.208 –0.257 (0.220); MPST = 0.214 –0.234 (0.224); PEL = 0.267 –0.305 (0.281); NOL = 0.153 –0.204 (0.180); NOH = 0.099 –0.118 (0.105); PEH = 0.189 –0.214 (0.196); PPL = 0.189 –0.229 (0.208); PPH = 0.239 –0.255 (0.248); PW = 0.343 –0.402 (0.371); SBPA = 0.137 –0.169 (0.154); SPTI = 0.176 –0.220 (0.196); PEW = 0.127 –0.146 (0.137); PNW = 0.117 –0.149 (0.133); PPW = 0.358 –0.392 (0.373); HFL = 0.444 –0.543 (0.491); HFWmax = 0.118 –0.162 (0.141); HFWmin = 0.044 –0.053 (0.050); CS = 0.775 –0.871 (0.822); ES = 0.170 –0.198 (0.183); SI = 91–99 (95); OI = 21–23 (22); CI = 80–83 (81); WLI = 133–141 (137); SBI = 28–31 (30); PSI = 28–39 (32); PWI = 249–295 (272); PLI = 118–150 (136); NI = 147–191 (171); PNWI = 92–102 (96); NLI = 53–76 (64); FI = 236–361 (287).

Worker description: In full-face view, head subquadrate, longer than broad (CI 80–83). Mandibles weakly striate, shining, and armed with five small teeth: the apical-most well developed, followed by a smaller preapical tooth, which is followed by three equally developed smaller teeth. Anterior clypeal margin entire and evenly rounded. Antennal scapes moderately long: when fully retracted, just reaching the posterior margin of the head capsule (SI 91–99). Antennae 12-segmented; antennal club of three segments, with the apical-most segment slightly longer than the preceding two in combination. Frontal carinae moderately long, extending past the antennal toruli by about two times the maximum width of the antennal scape. Compound eyes moderately protruding past the lateral margins of the head capsule. Lateral margin of head weakly convex, nearly flat, and forming a continuous arc from the posterior of the head to the mandibular insertions. Posterior head margin weakly concave but transitioning into the lateral margin through a rounded corner, giving the head a boxy appearance.

In profile view, compound eyes ovular, moderately large (OI 21–23), with 9 ommatidia in longest row. Pronotal declivity distinct, neck and anterior face of pronotum forming a ~110 ° angle; anterior and dorsal faces of pronotum forming a ~130 ° angle. Mesosoma very weakly convex from the pronotal declivity to the propodeal spines, nearly flat. Promesonotal suture extending from the posterior margin of the procoxal insertion only to the mesothoracic spiracle, which is well developed. Metanotal groove visible as a disruption of the sculpture laterally from where it arises between the mid- and hind coxae to where it ends in the poorly developed metathoracic spiracle, which is nearly indistinguishable against the ground sculpture. Propodeal spiracle poorly developed, directed posterolaterally, and separated from the propodeal declivity by about two spiracle diameters. Propodeal spines well developed and moderately long (PSI 28–39), about as long as the propodeal declivity, tapering evenly from the base, straight, and acute. Propodeal declivity weakly concave, forming a ~80 ° angle with the base of the propodeal spines. Propodeal lobes rounded and weakly developed. Metapleural gland bulla small, extending from the metacoxal insertion halfway to the propodeal spiracle. Petiole short (PLI 118–150), without tubercles anterodorsally. Subpetiolar process in the form of a small, acute tooth. Petiolar peduncle short: petiolar node covering most of the petiolar dorsum. Petiolar node robust: grading evenly into the petiolar peduncle anteriorly, resulting in a slightly concave anterior node face; anterior margin forming a ~100 ° angle with the dorsal surface, which is weakly convex; dorsal face rounding evenly into the short posterior face, which forms a ~110 ° angle with the caudal cylinder. Postpetiole evenly rounded anteriorly, flattened dorsally, and weakly lobed ventrally.

In dorsal view, humeri weakly developed: evenly rounded and slightly wider than the rest of the mesosoma; mesothoracic spiracles visible as a very slight angle where the pronotum meets the mesonotum. Metanotal groove absent: mesonotum and propodeum completely fused and converging evenly to the bases of the propodeal spines. Propodeal spines broadly approximated basally, but diverging apically, their apices separated from each other by about their length; negative space between them “U” shaped. Petiolar peduncle with spiracles slightly protruding past the lateral margins, and subtly constricted anterior to them. Petiolar node evenly ovular; node slightly wider than the peduncle, and evenly grading into the caudal cylinder, which is slightly wider than the node. Postpetiole very broad (PWI 249–295) and campaniform, articulating with the entire anterior margin of the gaster. Anterior margin of the postpetiole convex, evenly rounding into the lateral margins, which diverge to the angulate posterior corners; posterior margin broadly concave. Metafemur weakly to strongly incrassate (FI 236–361).

Sculpture: median clypeal carina present, extending posteriorly to the level of the antennal toruli, and flanked on either side by two equally strong carinae. Lateral clypeal lobes with additional, weaker carinae; ground sculpture smooth and shining. Antennal scapes shining through weak areolate ground sculpture. Cephalic dorsum evenly areolate, with the areolae arranged into longitudinal rows separated by costulae; ventral surface of head weakly areolate and shining. Pronotal neck areolate. Lateral surfaces of the pronotum shining, with weak rugulae. Mesopleurae and lateral surface of propodeum areolate. Propodeal declivity shining through weak areolate sculpture. Dorsal surface of mesosoma with costulae over areolate ground sculpture. Femora shining, with weak areolate sculpture on the distal third. Petiole smooth and shining ventrally, with weak areolate sculpture on all other surfaces. Postpetiole with weak areolate sculpture becoming stronger on the posterior third. Gaster smooth and shining, without spectral iridescence.

Setae: antennal scapes and funiculi with short, adpressed pilosity. Dorsum of head, pronotum, waist segments and gaster with moderately abundant, erect, blunt-tipped setae, the longest of which are about the length of the compound eye. The head bears ~28, mesosoma ~24, petiole 4, postpetiole ~18, and first gastral tergite ~48 setae. Short, sparse pubescence present over the entire body, but difficult to detect against the lightly colored integument.

Color: predominantly light yellow, with the masticatory margin of the mandibles darker.

Gyne measurements & indices (n = 2): SL = 0.567 –0.573 (0.570); FRS = 0.229 –0.249 (0.239); CW = 0.746 –0.764 (0.755); CWb = 0.703 –0.708 (0.706); PoOC = 0.295 –0.307 (0.301); CL = 0.728 –0.740 (0.734); EL = 0.208 –0.223 (0.216); EW = 0.173 –0.188 (0.181); MD = 0.160 –0.166 (0.163); WL = 1.157 –1.196 (1.177); SPST = 0.283 –0.308 (0.296); MPST = 0.285 –0.313 (0.299); PEL = 0.405 –0.413 (0.409); NOL = 0.169 –0.185 (0.177); NOH = 0.146 –0.152 (0.149); PEH = 0.279 –0.302 (0.291); PPL = 0.227 –0.234 (0.231); PPH = 0.319 –0.341 (0.330); PW = 0.703 –0.720 (0.712); SBPA = 0.314 –0.324 (0.319); SPTI = 0.32; PEW = 0.192 –0.197 (0.195); PNW = 0.228 –0.234 (0.231); PPW = 0.541 –0.550 (0.546); HFL = 0.631 –0.651 (0.641); HFWmax = 0.148 –0.150 (0.149); HFWmin = 0.058 –0.059 (0.059); CS = 1.072 –1.073 (1.073); ES = 0.295 –0.317 (0.306); SI = 81; OI = 27–30 (29); CI = 95–97 (96); WLI = 165–169 (167); SBI = 45–46 (45); PSI = 24–26 (25); PWI = 279–282 (280); PLI = 173–182 (178); NI = 111–127 (119); PNWI = 119–119 (119); NLI = 41–46 (43); FI = 254–255 (255).

Gyne description: In full-face view, head subquadrate, slightly longer than broad (CI 95–97). Mandibles weakly striate, shining, and armed with five small teeth: the apical-most well developed, followed by a less developed preapical tooth and three equally developed smaller teeth. Anterior clypeal margin flat medially. Antennal scapes moderately long: when fully retracted, just reaching the posterior margin of the head capsule (SI 81). Antennae 12-segmented; antennal club of three segments, with the apical-most segment slightly longer than the preceding two in combination. Frontal carinae very short, extending past the antennal toruli by two times the maximum width of the antennal scape. Compound eyes moderately protruding past the lateral margins of the head capsule. Lateral margins of head converging evenly from the expanded temples to the mandibular insertions. Posterior head margin concave medially, with temples rounding evenly into the lateral margins.

In profile view, compound eyes large (OI 27–30), ovular, with 16 ommatidia in longest row. Mesoscutum rounded evenly anteriorly, covering the dorsal surface of the pronotum, and flat dorsally. Mesoscutellum slightly depressed below the level of the mesoscutum, not overhanging the metanotum. Propodeal spiracle well developed, directed anteroposteriorly, and separated from the propodeal declivity by about four spiracle diameters. Propodeal spines stout and well developed, but short (PSI 24–26), about two thirds as long as the propodeal declivity, tapering evenly from the base, directed posteriorly, upturned, and blunt. Propodeal declivity weakly concave and forming a ~90 ° angle with the base of the propodeal spines. Propodeal lobes weakly developed, with the dorsal margin slightly angulate. Petiole moderately long (PLI 173–182), without tubercles anterodorsally. Subpetiolar process in the form of a small, very acute tooth, which grades evenly into the ventral margin of the petiole posteriorly; ventral margin of the petiole slightly bulging. Petiolar peduncle short: petiolar node covering most of the petiolar dorsum. Petiolar node erect: transition between peduncle and node evenly rounded, resulting in a very slightly concave anterior node face; anterior face forming a sharp ~100 ° angle with the dorsal face, which is short; dorsal face rounding evenly into the posterior face, which forms a ~140 ° angle with the caudal cylinder. Postpetiole evenly rounded anterodorsally, forming a slight convexity before it transitions into the flattened dorsal face; ventral surface lobed.

In dorsal view, mesoscutum covering pronotum anteriorly, but humeri visible laterally as rounded sclerites. Propodeal spines diverging apically, their apices separated from each other by about two times their length. Petiolar peduncle with spiracles slightly protruding past the lateral margins; node emarginated anterodorsally, dorsal face transitioning into the lateral faces with a rounded ~90 ° angle, which taper into the indistinct posterior face. Petiolar node slightly wider than the peduncle, and evenly grading into the caudal cylinder, which narrower than the node. Postpetiole very broad (PWI 279–282), anteroposteriorly compressed, and campaniform, articulating with most of the anterior margin of the gaster, leaving small, weakly angulate margins on each side exposed. Anterior margin of the postpetiole weakly convex, with corners evenly rounding into the lateral margins, which evenly diverge to the angulate posterior corners; posterior margin broadly concave. Metafemur moderately incrassate (FI 254–255).

Sculpture: median clypeal carina present, extending from the anterior margin to the level of the antennal toruli, and flanked two equally strong carinae. Lateral clypeal lobes with additional weaker carinae; ground sculpture smooth and shining. Antennal scapes shining through very weakly areolate ground sculpture. Cephalic dorsum shining with costulae over weak areolate ground sculpture; ventral surface of head shining through weak, indistinct areolate sculpture. Pronotal neck areolate. Pronotum with costulae over weak areolate ground sculpture. Anepisternum and katepisternum shining through weak areolate ground sculpture. Propodeum with weak areolae and costulae laterally; declivity areolate. Mesoscutum with weak costulae over weak areolate ground sculpture. Femora smooth and shining, with traces weak areolate sculpture distally. Peduncle of petiole smooth and shining ventrally, with shallow areolate sculpture on all other surfaces. Postpetiole weakly areolate. Gaster smooth and shining, without spectral iridescence. Surface of the first gastral sternite smooth and shining.

Setae: antennal scapes and funiculi with short, adpressed pilosity. Dorsum of head, pronotum, waist segments and gaster with moderately abundant, erect, blunt-tipped setae, the longest of which are about a third of the width of the compound eye. Short, sparse pubescence present over the entire body, but difficult to detect against the lightly colored integument.

Color: predominantly light yellow, with the masticatory margin of the mandibles and wing bases darker.

Male: Unknown.

Etymology: Behavioral, from Agave (plant genus) + ‘colere’ (dweller) from Latin, in reference to two collections of this species being made from dead stalks of Agave spp.

Comments: Temnothorax agavicola sp. nov. is known from three collections from southern Hispaniola, which were made from dead agave stalks and downed wood in a dry forest habitat. Other details of the biology of this species are unknown but are probably similar to other members of the terricolous pan-Caribbean pulchellus group. The specimens from the Turks and Caicos Islands vary morphologically from the Hispaniola material that I have examined; with more incrassate femora (the widest point of the hind femur 3 to 3.6 times as wide as the narrowest point vs. 2.4 to 3 in the Hispaniolan populations), overall larger body size (WL 0.73 to 0.75 mm vs. 0.66 to 0.69 mm), and more posteriorly directed propodeal spines, this population may prove to be different species ( Figs. 134G–134I ). A phylogenetic analysis provides evidence that these two populations are sister to each other (Prebus, in prep.).

Figures

Figure 133 Geographical and elevational distribution of the pulchellus group. (A) Temnothorax agavicola sp. nov. (B) T. albispinus. (C) T. bahoruco sp. nov. (D) T. balaclava sp. nov. (E) T. ciferrii (F) T. flavidulus (G) T. harlequina sp. nov. (H) T. hippolytus sp. nov. (I) T. laticrus sp. nov. (J) T. magnabulla sp. nov. (K) T. pulchellus (L) T. terricola (M) T. torrei (N) T. wettereri sp. nov. (O) T. wilsoni sp. nov. Colored scale to the left of each map represents elevation in meters. Points in black represent the species named in each subfigure, while points in red represent other members of the species group. Type localities are represented by triangles; if present, types of synonyms are named; non-type localities are represented by circles. Bounding box in inset map shows location of main map. Full-size DOI: 10.7717/peerj.11514/fig-133

Figure 134 Temnothorax agavicola sp. nov. (A-C) Holotype worker (MCZENT00510559). (A) Fullface view. (B) Profile view. (C) Dorsal view. (D–F) Paratype gyne (MCZENT00510541). (D) Full-face view. (E) Profile view. (F) Dorsal view. (G–I) Morphological variant, Providenciales, Turks and Caicos Islands (CASENT0756096). (G) Full-face view. (H) Profile view. (I) Dorsal view. Scale bars 0.2 mm. Full-size DOI: 10.7717/peerj.11514/fig-134